Steam process for fixing coloring material in textile goods



WEHRLI STEAM PROCESS FOR FIXING COLORING Aug. 3, 1948. J.

MATERIAL IN TEXTILE GOODS Filed March 9, 1944 3mm ean WeAkZL l atented Aug. 3, 1948 STEAM PROCESS FOR FIXINGCOLORING MATERIAL IN TEXTILE GOODS Jean Wehrli, Weinfelden, Switzerland Application March 9, 1944, Serial No. 525,694

' In Switzerland January 22, 1943 12 Claims. 1

According to the methods used heretofore for dyeing and printing fabrics, in the former case the principle adopted was to charge the fabrics to be dyed with more or less dissolved colouring matter, by gradual steps, until the desired color was obtained. In order to accelerate this method the process is usually carried out under fairly high temperatures, according to the colouring material used. All processes of this type require a comparatively long treatment and, therefore, the heat consumed is considerable. In the case of normal printing methods, the colours are applied in a more or less intensive manner and, in one case, they are subsequently exposed to the action of steam, in order to effect a fixing of the dye on the fibre. However, by such means a deep penetration of the colouring material into the fibres cannot be obtained and, for this reason, uniform colouring of the fibres is not possible, generally speaking, particularly in the case of compact tissues.

The problem of colouring material penetrating as deeply as possible into the fibres, either applied by a dyeing or by a printing step has not heretofore been solved in a technically satisfactory manner. It was ascertained with some surprise that, when dyeing or printing textile goods of every description, for instance, yarns, tissues, knitted and woven textile materials or webs, of natural or of artificial fibres, a far deeper penetration of the colouring material into the fibre and, thereby, a better fixation of the colouring matters was obtained, if the textile goods to be dyed or printed, which had been treated beforehand with colouring material in the well known manner, was exposed to a treatment by wet steam in a container by means ofalternate low and high pressure, and then subjected to further treatment in the usual way. The change of pressure is advantageously effected in rapid succession. Thereby, it is possible to produce a deep impregnation effect within a relatively short space of time. If the low pressure lies in the vacuum range, the vacuum pressure can be produced by condensation of the steam from the higher pressure. When dyeing or impregnating, the dyers bath or impregnating solution can be let in the container at vacuum pressure, and the liquor may be subsequently circulated in vacuum condition. 5 After removal of the liquor, the container is filled with the steam under higher pressure. This treatment can be repeated. Subsequent to the treatment of the liquor, the amount, pressure and temperature respectively of the steam supply can be influenced and regulated by simultaneous continuation of the process by condensation.

The change of the low pressure into the vacuum region is carried out under an automatic ventilation of the tissue. The single fibres of the material first swell, when they are under treatment by steam, whereby at least a part of the air in the fibres is removed. In the followingvacuum stage, the remaining air contained in the fibre is removed and,due to the pressure treatment then immediately following, the single par-.- ticlesof the colouring material, or of the impregnating material, are forced into the hollow spaces of the fibres, which are now devoid of air. Then, during the alternate pressure and vacuum treatments, the dye is pumped into the fibres in an increasingly stronger manner. If the low pressure is changed into the region of pressures above the atmospheric pressure, this method can be rendered more economical, inasmuch as an important saving of steam can be attained. Condensation of steam is reduced, and the consump-w tion of steam is, therefore, also considerably reduced. As compared with the constant pressure damping process so far known, a pronounced saving of time is attained. It is of advantage, when starting the steam treatment, to remove the air from the tissue by means of an intensive current of steam through the material to be treated. It is appropriate to lead steam to the material to be treated, either from the interior to the exterior, or vice versa, or, in a given case, alternately.

, By way of example, the following is an illustration of the method described according to the present invention:

First emample.--A compact piece of textile material with cellular wool in the warp and artificial silk in the woof was subjected to a preliminary treatment and dried in the usual manner. Subsequently, it was padded on a Foulard-machine at 90 C. with benzc fast copper red colour (1 mol. 4-4-diaminodiphenyl-3-3-dioxyacetic acid diazo tized'and coupled with 2 mol. l-phenyl-S-m'ethylfi-aminopyrazol) and an addition of wetting means. The intermediately dried or wet tissue was then transferred to a pressure-container, and the latter was filled with wet steam of low pressure, for instance, 0.2 at. above the atmospheric pressure. Subsequently, a vacuum was produced,

I for instance, up to 80%, and then an immediate treatment in a pressure-container; such alternate steps taking place for 8-20 minutes and, subse= quently, it was treated in the usual manner.

The tissue showed far more intense colours and much stronger impregnation: as compared with: tissues treated during the same period .of time;

with the same amount of colouring material. and.

subjected to the steam-treatment, which had been in use up to the present.

Third eaec'mpla- Alieavy'twilled tissue consisting of cellular wool and cottonised hemp'in the warp,-- and cellular wool in the woof, was subjcctedto a preliminarytreatment in the ordinary way and then dried. Subsequently, it'was treated during passage through a Fciulard-machine at 90 0.; by means of colouring matters and an addition of wetting means. The intermediately dried or wet tissuewas then transferred to a container, and the latter filled withsteain of, for instance,- 1 at'pabove' the atmospheric pressure. Subsequently', the mixture of steam-air was blown out, bymeansof a strongcurrent, until the steampressure-ha'dbeen reduced to about 0.4 at. above the: atmospheric pressure. Following. these steps, the steam-pressure was subjected to rapid changes between 0.4 and 0.8 at. above theatmospheric pressure,-- approximately eight times within 6 minutes. The entire treatment was eftested by steam in saturated-condition. I Th tis-' we was then further-treated in the usualmannet. The material treated i this way showed uniform and completely impregnated woofthreadslan-d warp-threeds oifar more intense colouri-ng hades than the colours developed-on theji-g-ger.

By the-process-accord-ing to the present invention-,--a considerable shortening of the time required fordyelng is attained and, thereby, also a considerable saving-of heat energy and of colcuring materials, apart from the intense impregnation oft-he fibre byt-he colouring materials. then damping impressions according to the pres ent invention, effects can be accomplished; which are surprising and could not be attalnedheretofore by applying the same amountofcolouring materials.

The same effect canalso be attained if an impregnation of the textile goods is carried out in the-manner described either independently, or simultaneously with the dyeingor. impregnatins-procedure.

In". the drawing; a section through. an apparatu'sis illustrated by. Way of example, in which the. inventive method. can be carried out.

A sealed container. i has a bottom 2. into which acentrally located pipe 3 extends. Said. pipe has athreaded upper end 4 inside of said container l. A reel or spool 5 can be. removabl-y mounted on saldthreaded portion, 4. by means. of its correspondingly threaded lower endor hub 6. The reel :or spool 5 has-a cylinder l provided with a numberof openings 8. The cylinder 1. may be conveniently made of perforated-sheet metal; A

4 piece or web 9 of the textile material to be treated can be spirally wound on said cylinder 1.

The top of the container l is closed by it hermetically sealing cover or lid I!) which can be readily opened when the reel or spool 5 is introduced into the container or removed therefrom. A pipe I l ends in the upper part of the wall of the conta-iner L'said pipe I I having a three-way cock I2, through which the pipe can be selectively connected either with a live steam feed conduit l3 or an exhaust steam conduit M.

The central pipe 3 can be selectively connected with a live steam feed conduit [6 or an exhaust steam conduit l'l through a three-way cock IS. A feed pipe l8 and a pipe 20 connect the central pipe 3 with a vessel or tank [9 containing the 'dyefls bath. Said vessel or tank I9 is connected with pipe 22 ending in the bottom 2 of the containerl through pipe 20 and a circulating pump 2 l. In each of the pipes 18, 20 and 22 stop cocks l8a, 20c and 22a respectively are inserted.

Before. the apparatus is operated,- the reelor spool 5,-=on which a web of textile material" 9 is wound, is introduced through the open'top of. the container i and the hub G of said reel or spool 5 is firmly screwed on the upper end 4 ofthe pipe 3-. The container t is then hermetically closedby the cover ID. The three-way cocks l5 and I2 are turnedto the positions shown in thedrawl-ne. Live steam is now streamingthrough the conduit 16, the three-way cock l5, the pipe ii -interior oi the reel or spool 5, openings 8 of cylinder 1, textile material 9 into container I and escapes from there through the pipe ll, three-way cock 12 to the exhaust pipe. l4. The steam is passed through the textile; material 9 until the air is entirely removed therefrom. Thereafter, the three-way cocks l5 and I2 are turned to positions inswhich they shut off the container 1 com pletely. To accomplish this, threeway cock [5 has to be turned counterclockwise-,while the. cock l2 has to be turned During this operation,. the steam feed conduits I6 and were shut off by separate valves, not shown in. the drawings. A cold water feed pipe 25 supplies water to an annular tube 20, surrounding the container l, a shut oli valve 23a being inserted in said feed pipe. 2-5." The annular tube 24 is provided with a number of nozzles 23 which are directed against the wall of the. container l in such a manner that wheat-he shut-off valve 2.3a. is opened, said contamer l lssprayed with cold water and thereby cooled. so that: the steam in the interior of the container l is condensed. As a result of this, .a. vacuum is created inside ofthe container- 1 opening the most inner pores or interstices of the fibres of the-textilematerial 9. Thereafter, the stop cocks l8aand 20a are opened so that. the dyers bath in. the. vessel or tank I9 which is. under. atmospheric pressure is sucked throughthe pipes 20; I8 and 3 into the'iinteri'or oi the reel or spool 5 under the action of the vacuum and streams through the openings Bfand the textile material 9' into the container t; filling" the latter completely: The stop cock 20d is now closed-and the stop cock Z-Zc opened. Thereafter; the pump 2] is put' into operation, circulating the dyers bath; in the direction 01 the" arrow iin 'pipe' 2-2) through the; pipes222, t8; 3; theireelor spool-fi, theopenings lhthe textile goods 9;. the container 1, and back to the'; pipe 22, wherebythe dyers bath is repeatedly passed through the textile material 9 until a sufiicien-t. impregnation-or. dyeing isobtained. Thereaftenthe stopcock I-Bcls shut off-andthe three-way cock 1-2 is returned to the 5 position shown in the drawing. The stop cock 20a is now opened and the pump 2| pumps the dyers bath back to the vessel or tank I9 through the pipes 22, 25 and the stop cock 20a. After return of the dyers bath, the stop cocks 20a and 22a are again closed.

The textile material 8 is now impregnated or dyed'with the coloring substance, which has to be fixed in the fibres. To accomplish this, the three-way cook 85 is returned to the position shown in the drawing. Wet steam is now fed to the container I through the pipe I6, the three- Way cock I5, the pipe 3, the interior of the reel or spool'5, the opening 8, the textile material 9 and is passed from there through the pipe I I, the three-way cock I2 to the exhaust pipe I4, the direction of the steam being indicated by arrows. After the textile material 9 has been intensively treated by the wet steam passing therethrough in this manner, the two three-way cocks I2 and I5 are turned to positions in which they completely shut off the container I." By opening the valve 23w cooling water is passed through the nozzles 23 so that the outside of the container I is sprayed with cold water with the result that the steam inside the container I is condensed and a pressure drop obtained within said container I. Immediately thereafter, the valve 23a is closed and the three-way cock I5 is opened, so that again wet steam enters the container I through the pipe I6, three-Way cock I5, pipe 3, reel or spool 5 and textile material 9, whereby the original pressure in the interior of the container I is obtained. When this has taken place, the three-way cock I5 is turned to closing position shutting oh the container I. The cool water valve 23a is now opened so that the coolin water sprays through the nozzles 23 on the container I resulting in a pressure drop Within said container. The pressure change or variation steps can be repeated any number of times, whereby care has to be taken that the steam in the interior of the container I remains markedly wet during the whole fixation step, because the fixation effect of the high quality of the inventive process can only be obtained if steam remaining wet during the whole treatment is acted upon the textile goods under repeated pressure change or variation.

The fixing action can be still more intensified by operating the three-way cocks I5 and I2 alternately, rather than the three-way cock I 5 alone to restore the pressure, whereby at each operation the three-way cock previously used is turned to a position shutting off the container I. As a result of this alternate operation of the two three-way cooks, the wet steam is passed alternately through the textile material 9 in the one and in the other direction, 1. e., from the interior of the reel or spool 5 outwardly through the openings 8 and the textile material 9 in the direction of the arrows and then in the opposite direction. If the steam shall be solely passed in the opposite direction of the arrows, i. e., from the container I inwardly towards the interior of the reel or spool 5, only the threeway cock I2 has to be operated.

After the color has been sufiiciently fixed, the steam supply is shut on, the cover I opened, the reel or spool '5 unscrewed from the threaded upper end 4 of pipe 3 and removed from the container I. After a new reel or spool wound with untreated textile material has been introduced into the container I, the process can be repeated as described.

If a spool carrying textile goods previously loaded with coloring substances, for example, by padding or printing, is introduced into the container I, the dyeing step is omitted and only the fixing step is carried out, whereby the steam will be passed through the textilematerialeither in the one or the other direction, or alternately in both directions as described. In this case, it is very important that the steam used for thefixing step is and remains markedly wet throughout this operation, because the coloring substances previously applied to the textile goods adhere to the fibres more or less superficially and the textile goods are ordinarily dried after the color loading step. Consequentl it is essential that markedly wet steam is employed to fix the coloring substances inthe fibres and that the wet condition of the steam is constantly checked during the operation, as the textile goods practically do not contain any moisture.

What I claim is:

1. A process for fixing coloring materials in textile goods comprising passing steam through the textile goods carrying the unfixed coloring materials until the air is entirely removed from said goods, shutting ofi the steam supply, evacuating the textile goods, passing wet steam through the textile goods, and varying the steam pressure alternately several times between higher and lower ranges.

2. A process for fixing coloring materials in textile goods comprising passing steam through the textile goods carrying the unfixed coloring materials until the air is entirely removed from said goods, shutting off the steam supply, evacuating the textile goods, passing wet steam through the textile goods, and varyin the steam pressure alternately several times between higher and lower ranges, the differences between said ranges being at least .4 atmosphere.

3. A process for dyeing textile goods, comprising treating said goods with steam, subjecting them to a vacuum produced by condensing the steam, introducing coloring liquor into said goods by the suction action of the vacuum and thereby dyeing them, removing the coloring liquor from the treated goods, fixing the coloring substances retained in the goods by the previous dyeing step by passing wet steam through the goods and varying the steam pressure alternately several times between higher and lower ranges.

4. A process for dyeing textile goods comprising treating said goods with steam, subjecting them to a vacuum produced by condensing the steam, introducing coloring liquor into said goods by the suction action of the vacuum and thereby dyeing them, removing the COIOI'ing liquor from the treated goods, fixing the coloring substances retained in the goods by the previous dyeing step by passing wet steam through the goods, and varying the steam pressure alternately several times between higher and lower ranges, the differences between said ranges being at least .4 atmosphere.

5. A process according to claim 1, in which the lower pressure is produced by condensation of the steam while the steam supply is shut off.

6. A process according to claim 1, in which the lower pressure is above atmospheric pressure.

7. A process according to claim 1, in which the pressure variations between higher and lower ranges are effected at the rate of approximately 8 times within 6 minutes.

8. A process according to claim 2, in which the pressure of the wet steam is varied between vacmimiand' one atmosphere above atmospheric pressure 7 9. A process according to claim 1 in which the steam is passed t'hrough the textile goods in one direction.

10. A process'according to claim 1, in which the steam'is passedthrough the textile goods alternately in the one and the other direction.

11. A process according to claim 1, in which the pressure of the wet steam is rapidly varied between .4 atmosphere above the atmospheric pressure and -.8 atmosphere above the atmospheric pressure.

12. Aprocess accordin to claim 3, in which the coloring liquor .-is circulated. during the vacuums'tep JEAN WEHRLI.

REFERENCES C IT-ED The following references are of record in the fileo'f this patent:

Number Number STATES PATENTS Name Date Haupt Jan. 25, 1870 Smith Nov. 11, 1879 Patterson Nov. 7, 1905 Hviid 1 July 22, 1919 Davis'et a1 Apr. 12, 1921 Min-ton Aug. 10, 1926 Pearce Aug. 6, 1929 Addy et a1 Jan. 7, 1930 Buhlmann Dec. 30, 1930 Chapin et all. June '7, 1932 Shidrowitz June 18, 1935 Greiser -1. Jan. 2 5, 1938 Bright. Aug. 6, 1940 FOREIGN PATENTS- Country Date Great Britain 1902 Great Britain 1894 Gieat- Britairl Dec. 6, 1936 

